In a typical lens barrel for a camera, an outer diameter of a lens is relatively large, and therefore, the lens barrel is manufactured by holding a sidewall section of the lens with tweezers to drop the lens in a barrel frame. Alternatively, instead of using tweezers, a lens is held sucked by a suction pad by vacuuming air, and such suction of the lens is disclosed in various patent documents.
For example, in order to assemble an object lens to a barrel frame, there is known a configuration to suck the object lens on a tray, one by one, with the suction pad (see patent document 1).
Moreover, for the purpose of correction of position of an optical element, there is known a configuration to suck an optical element with a rubber buffer ring (see patent document 2).